The offices of Cambridge Community Television are lit up with neon and klieg lights, a beacon to passersby who pause to peer through the wall of glass. A CCTV sign glows pink. Winking monitors flash the station's three channels.

In front there, that's David Stern, hard to miss in a red T-shirt and straw hat. He's about ready to go live with "Shootin' the Breeze," his off-the-cuff weather-cum-humor show. And over in the corner room, the "drive-by gallery," those are Cambridge residents planning their monthly public-affairs news magazine.

It's a typical and bustling evening here at this public-access TV station, where aspiring entertainers and concerned citizens congregate daily to put their messages out to the city. An idiosyncratic patchwork of programming, public access encompasses everything from quirky call-in shows to religious services to live music.

For many viewers, local-access channels are mere speed bumps on the dial between ABC and HBO. But for the people here tonight - and countless others at over a thousand stations around the country - these airwaves, available to all for a nominal fee, have become what Anthony Riddle, executive director of the Alliance for Community Media in Washington, calls "the public square in the electronic age."

That square could soon shrink. Congress is looking at legislation which, while opening cable to competition and greater options, may erode the main revenue stream for CCTV and many of its sibling stations across the country.

But that takes a back seat tonight. On this Monday evening, Jamila Newton is firmly focused on her 30-minute show. Through a small window in CCTV's Edit Room Two, the back of her long, dark braids just visible, she can be seen reviewing footage from "Bandwidth TV," a showcase for local musicians.

By day she's a graduate student in molecular and cell biology at nearby Harvard University. It was as an undergraduate in California that Ms. Newton first got a taste of local broadcasting. She was a DJ at her college's radio station. For Newton, the allure of public TV is that it lets her "take one band and give them more than their 15 minutes of fame," she says.

There are three types of cable, or local, access: public, educational, and governmental. It's on public access that local residents exhibit their work - sometimes inspired, sometimes ridiculous.

At Nutmeg TV in Plainville, Conn., which reaches eight local towns, a viewer can find "Space Age Times," a show that explores space and NASA. "The Art of the Bonsai" explains how to care for the small trees.

In Enid, Okla., on Pegasys, shows like "Take a Ride on the Chisholm Trail" plumb local history. And the "Postcard Show" features a collector who shares the story behind each of his postcards.

Taped in New Jersey at Princeton Community Television and aired on public-access channels throughout the country, "A Fistful of Popcorn" revolves around a panel of local residents who discuss art films.

And this summer, 13- to 25-year-olds in Grand Rapids, Mich., produced the feature-length film called "Kara in Black." This fictional account tells the story of the conflict between two sisters, one who joins the Army while the other is strongly antiwar.

Mr. Riddle, whose organization represents 3,000 channels, estimates that more than 30 percent of programming is religious; 30 percent or so is civic; at least 20 percent is creative, including things like teleplays and children's fashion shows; and another 15 percent is dedicated to sports.

TV for immigrants

In 1984, under the provisions of the Cable Act, public-access stations began in earnest. Historically, community television has been a forum particularly friendly to immigrants and minorities, groups regularly overlooked by the larger networks. (Manhattan alone has 95 foreign-language serials on public-access TV.)

In the late '80s, a group of Hmong refugees from Asia were resettled in the Minneapolis- St. Paul area. Their resettlement classes happened to be held in the same converted school building that housed the public-access station.

A people with a strong oral tradition who for centuries had no written language, they learned to connect with one another via video, one year filming 24 hours of a New Year's celebration. Surveys showed that virtually every one of the 25,000 Hmong in the area at the time watched public access.

While general viewership might not be so high - there are no Nielsen ratings for public-access channels - the program creators don't seem to mind. Mr. Stern, host of the weekly weather show in Cambridge, says he first got involved with public access "to find an outlet for [his] artistic expression." The pianist and composer once produced a 30-minute segment on a chef at the Green Street Grill, a local restaurant. "Exploring Expression," which searched for "the spiritual connection" to food, was meant to be part of a series. But that first, and last, episode took six months to make - roughly 10 hours for each minute that aired.

Stern compares CCTV to a coffee shop. "It's an inspiring place, a bustling place," he says. "It keeps one motivated and focused. There are a lot of young people who come in and try to do shows. Some succeed, some don't. But it's a great way for young people to aspire - they're surrounded by people who are doing wonderful things."

Last year, more than 17,000hours of original, local programming appeared on CCTV.

Proponents of the three amendments before Congress, which include "The Broadband Investment and Consumer Choice Act," introduced by Sen. John Ensign (R) of Nevada and supported by Sen. John McCain (R) of Arizona, say the purpose is to reform outdated laws and open the telecom market - now dominated by cable companies - to competition from other providers such as phone companies. Many directors of community television stations say that without franchise fees, which may be lost in the new legislation, they won't be able to survive.

Brownout ahead

Next month, CCTV's pink neon sign will be masked, the station's windows shrouded in brown paper. In an effort to show what they fear may happen if the bills before Congress are passed, CCTV has planned a brownout for Oct. 17.

On 25,000 televisions across Cambridge, Channels 9, 10, and 22 will go dark.

Go public

Want your own TV show? Most stations require local residents to attend an orientation session and pay a small annual fee.

Membership may include workshops on everything from operating cameras and lighting equipment to digital editing, plus access to the station and its equipment.

As a rule, stations are open to all local residents. They will usually accept both single shows and serials. And members may sponsor programs produced outside the community.

Local access is nonprofit and commercial-free, which is why stations rely so heavily on the franchise fees that cable providers have been required to funnel back into communities as payment for using streets and other public rights-of-way to lay their wires.